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Gravitational Entropy

  1. Dec 31, 2008 #1
    In Earth science there is a paradox of the 100-kyr orbital eccentricity of the Earth about the Sun. The Greenland and Antarctic ice cores show that the 100-kyr cycle is the most dominent in driving the advance and retreat of the ice ages. But the solar radiation increase is universally excepted to be too small to be the direct driving force. Similarly the gravitational difference of around a 6% change in eccentricity is considered too small to influence the tides in a significant way. There is a possibility though that this tidal effect could be amplified if the Earth is considered to have a gravitational entropy gradient. By this I mean that the gravitational force experienced by matter increases towards the center of the Earth i.e. it is non-linear. This is not to be confused with a simple increase in density. It is the entropy of matter itself which I propose is reducing towards the center of the Earth. Has anyone ever thought of this before? I can't find any reports on this hypothesis. Can anyone help?
  2. jcsd
  3. Dec 31, 2008 #2


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    According to who?

    As it turns out, the gravitational force on a given object decreases towards the center of the earth (it is exactly zero at the center).

    If I'm not mistaken, the gravitational field decreases with diminishing radial distance from the center of a sphere no matter what the radial density distribution of the sphere. In any case, it decreases linearly for a planet of uniform density.

    The entropy of matter is virtually unaffected by terrestrial gravitational fields. Besides, personal theories and speculation therefrom are not permitted here.
    Last edited: Jan 1, 2009
  4. Dec 31, 2008 #3

    Lot's more complicated paradox's exist than you mention!!!

    when I first heard about man made global warming I started studying to see what was known (very little) and what was unknown ( a lot). There are many, many more "cycles" than you mention, many more factors than have been properly modeled. Their significance is not universally understood.

    The fact is that no one knows how to predict next weeks weather let alone the beginnings of the next ice age. Nor the movements of the ice sheets, For example, As I understand things, todays placement of the continents as a result of eons of drift has a potentially significant effect on warming/cooling since different locations get varying amounts of solar heat....and land and water absorb/reflect heat very differently.

    Also I found it interesting that some history of the earth shows life emerging, then being almost extinguished via vast ice sheets which encircled the earth to a depth of perhaps miles...yet something caused those to retreat and modern lifeforms emerged....with merely the artic and antarctic ice sheets remaining....

    Earth's tilt on it's axis is another factor that comes to mind...and sunspot activity...
  5. Dec 31, 2008 #4

    Just curious. How is this proven/known?
    Last edited: Dec 31, 2008
  6. Dec 31, 2008 #5

    Vanadium 50

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    Integral calculus.
  7. Dec 31, 2008 #6
    Gauss' law is quite nicely applicable here; although normally used for electric fields, i think it holds perfectly well for gravity since both fields are inversely squared proportional to distance. Just swap the right parameters and constants: charge with mass, etc.
  8. Jan 2, 2009 #7
    Naty1, thank you. Someone who is on our wavelength. Paleoclimatology is a fascinating subject which I have been studying over the last 4 months or so. There is so much confusion and so much which is simply unknown. It reminded me of the current situation with modern physics. Hence I made a connection between the two. Andre and I are battling out the data and theories in the Earth Science section. Background reading is essential to get to grips with this subject, I recommend 'The Two Mile Time Machine' by Richard Alley and the original text 'Ice Ages: Solving The Mystery' by Imbrie and Imbrie. I've come from a physics background and have been formulating the concept of gravitational entropy for years. It simply means that the tidal bulge becomes exaggerated with reducing distance and fits like a glove to solve both the 100-kyr eccentricity cycle and the millennial cycle.

    A quick link is given here Earth science thread which then has links to specific reports.
    Last edited: Jan 2, 2009
  9. Jan 2, 2009 #8


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    Any physics present in this thread has been covered.

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